Circuit board and power conversion apparatus having circuit board

ABSTRACT

The present invention discloses a circuit board, including a substrate and a magnetic core, where the magnetic core is embedded into the substrate, at least one turn of a winding conductor wound around the magnetic core is arranged on the substrate, each turn of the winding conductor includes a first end-surface conductor and a second end-surface conductor that are separately arranged on two ends of the magnetic core, and each turn of the winding conductor further includes a first side-surface conductor that penetrates through the magnetic core from an inner side of the magnetic core and a second side-surface conductor that penetrates through the magnetic core from an outer side of the magnetic core. The circuit board and the power conversion apparatus having the circuit board provided by the present invention, achieve larger inductance, save materials, and reduce cost for fabricating a power conversion apparatus.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/308,960, filed on Jun. 19, 2014, which is a continuation ofInternational Application No. PCT/CN2013/084549, filed on Sep. 28, 2013,which claims priority to Chinese Patent Application No. 201310189983.3,filed on May 21, 2013, The afore-mentioned patent applications arehereby incorporated by reference in their entireties.

TECHNICAL FIELD

The present invention relates to the field of electronic communicationstechnologies, and in particular, to a circuit board and a powerconversion apparatus having the circuit board.

BACKGROUND

Dramatic development of the information industry not only provides ahuge market and fast-growing force for the power supply industry, butalso imposes higher requirements on an installation volume, a weight,efficiency, and output dynamic performance of a power conversionapparatus, and reliability of a system thereof, and the like. “Short,small, light, and thin” is one of major development trends of a powerconversion apparatus nowadays.

A magnetic core component on a circuit board of a power conversionapparatus is the largest power component among modular power supplies,which occupies more than 20-30% of a projected area and exerts a greaterimpact on an appearance structure of a module and a layout of acomponent. Therefore, people are increasingly concerned about researchon a technology related to a magnetic core component and research onhigh density and compactness of a module.

To achieve high density and compactness, in the prior art, a discretemagnetic core inductor vertically stands on an upper surface of asubstrate, a usage area of the substrate is reduced by using athree-dimensional encapsulation structure and by using a space in avertical direction, thereby reducing an overall volume and improvingpower density thereof. The power conversion apparatus uses thethree-dimensional encapsulation structure, where a discrete inductor ismounted on a substrate, thereby reducing a horizontal area of thesubstrate. A shield layer is arranged between the inductor and thesubstrate, achieving an objective of reducing electromagneticinterference. In this technology, an independent inductor and acorresponding shield layer are used, and meanwhile, components on thesubstrate are encapsulated, so that cost of the power module is high. Inanother prior art, a magnetic core is arranged on a substrate, and apower circuit module of an indicator is fabricated by directly platingcopper on a surface of an inner ring of the annular magnetic core andwinding the magnetic core around a via hole around an outer ring of themagnetic core. In this technology, a plated-through hole is arranged onthe substrate, the annular magnetic core is placed in the plated-throughhole, and a conductive copper layer is formed by directly plating on aninner side wall of the annular magnetic core, a winding of the inductoris formed in combination with winding with the copper wire on thesurface of the substrate, and a power circuit with the embedded inductoris used. In this technology, the winding of the magnetic core travelsonly through the surface of the inner ring of the magnetic core.Therefore, the inductor has only one turn of wire, and an inductancevalue is small. In addition, because the embedment-type winding manneris used, the embedded magnetic core has a single shape, that is, anannular shape, which cannot meet a requirement during actualapplications.

In conclusion, in the prior art, the power conversion apparatus uses anindependent inductor and a corresponding shield layer; and meanwhile,the components on the substrate are encapsulated. As a result, the costof the circuit board is high. In addition, in the prior art, the windingof the magnetic core travels only through the surface of the inner ringof the magnetic core. Therefore, the magnetic core has only one turn ofwire, and the inductance value is small, the embedded magnetic core hasa single shape, which cannot meet a requirement for large inductanceduring actual applications.

SUMMARY

An objective of the present invention is to address the foregoingdisadvantages of the prior art, and to provide a circuit board and apower conversion apparatus having the circuit board, where noindependent inductor or no corresponding shield layer needs to bearranged, thereby reducing cost. Meanwhile, the number of turns ofwinding may be set to one turn, two turns or even more turns, and aninductance value may be designed to a larger value. Therefore, a usagerequirement under an actual condition of larger inductance may be met,and the cost is low.

According to a first aspect, the present invention provides a circuitboard, including a substrate and a magnetic core, where the magneticcore is in an annular shape and the magnetic core includes an inner sideand an outer side, where the magnetic core is embedded into thesubstrate, at least one turn of a winding conductor wound around themagnetic core is arranged on the substrate, each turn of the windingconductor includes a first end-surface conductor and a secondend-surface conductor that are separately arranged on two ends of themagnetic core, and each turn of the winding conductor further includes afirst side-surface conductor that penetrates through the inner side ofthe magnetic core or penetrates through and arranged on the inner sideof the magnetic core and a second side-surface conductor that isarranged on the outer side of the magnetic core, where the firstside-surface conductor is electrically connected to the firstend-surface conductor and the second end-surface conductor, and thesecond side-surface conductor is electrically connected to the firstend-surface conductor.

With reference to the first aspect, in a first possible implementationmanner, the first end-surface conductor is arranged on one end surfaceof the substrate, and the second end-surface conductor is arranged onthe other end surface of the substrate.

With reference to the first aspect, in a second possible implementationmanner, a first via hole is arranged on the substrate, where the firstvia hole is located on the inner side of the magnetic core, and thefirst side-surface conductor is a conductor filled in the first viahole; or a first plated-through hole that is penetrates through andarranged on the inner side of the magnetic core is arranged on thesubstrate, and the first side-surface conductor is a conductor that isplated on an inner side wall of the first plated-through hole.

With reference to the first aspect, in a third possible implementationmanner, a second via hole is arranged on the substrate, where the secondvia hole is located on the outer side of the magnetic core, and thesecond side-surface conductor is a conductor that is filled in thesecond via hole; or a second plated-through hole is arranged on thesubstrate, where the second plated-through hole is located on the outerside of the magnetic core, and the second side-surface conductor is aconductor that is plated on an inner side wall of the secondplated-through hole.

With reference to the first aspect, in a fourth possible implementationmanner, the second side-surface conductor is a conductor that is platedon a side wall of the substrate.

With reference to the first aspect, in a fifth possible implementationmanner, the magnetic core is vertically or horizontally embedded intothe substrate.

With reference to the first aspect, in a sixth possible implementationmanner, the magnetic core is in an annular shape, a polygonal annularshape, a combined shape of a “U” shape and an “I” shape, a combinedshape of an “E” shape and an “I” shape, or a combined shape of an “E”shape and another “E” shape.

With reference to the first aspect, in a seventh possible implementationmanner, the magnetic core is in a polygonal annular shape and themagnetic core has a plurality of head-tail connected edges; the windingconductor has at least two turns, where at least one turn of the windingconductor is wound around one edge of the magnetic core and at least theother one turn of the winding conductor is wound around another edge ofthe magnetic core; or all the winding conductor is wound around a sameedge of the magnetic core.

With reference to the first aspect, in a eighth possible implementationmanner, top and bottom ends of the substrate are end surfaces, where theend surfaces include a front surface and a rear surface that areoppositely arranged, and an outer peripheral wall of the substrate is aside surface of the substrate; an area formed by projection of themagnetic core on the front surface or rear surface of the substrate isan area in which the magnetic core is located; the first end-surfaceconductor is arranged on the front surface of the substrate, and thesecond end-surface conductor is arranged on the rear surface of thesubstrate; the winding conductor has at least two turns, including afirst turn of the winding conductor and a second turn of the windingconductor, a first electronic component is arranged on the front surfaceof the substrate, and the magnetic core is horizontally arranged, wherethe first electronic component is located outside the area in which themagnetic core is located; the first end-surface conductor of the firstturn of the winding conductor is connected to the first electroniccomponent and extends to the area in which the magnetic core is located,the first side-surface conductor of the first turn of the windingconductor is a first conductive via hole, the first end-surfaceconductor of the first turn of the winding conductor is electricallyconductive to a metal layer of the rear surface of the substrate throughthe first conductive via hole, the second end-surface conductor of thefirst turn of the winding conductor is connected to the firstside-surface conductor of the first turn of the winding conductor,extends to the side surface of the substrate, and is connected to thesecond side-surface conductor, and the second side-surface conductor ofthe first turn of the winding conductor is arranged on the side surfaceof the substrate and connected to the second end-surface conductor ofthe second turn of the winding conductor; the first end-surfaceconductor of the second turn of the winding conductor is connected tothe second side-surface conductor of the first turn of the windingconductor and extends to the area in which the magnetic core is located,the first side-surface conductor of the second turn of the windingconductor is a second conductive via hole, the first end-surfaceconductor of the second turn of the winding conductor is electricallyconductive to the metal layer of the rear surface of the substratethrough the second conductive via hole, the second end-surface conductorof the second turn of the winding conductor is connected to the firstside-surface conductor of the second turn of the winding conductor andextends to the side surface of the substrate, and the secondside-surface conductor of the second turn of the winding conductor isarranged on the side surface of the substrate and connected to thesecond end-surface conductor of the first turn of the winding conductor.

With reference to the first aspect, in a ninth possible implementationmanner, top and bottom ends of the substrate are end surfaces, where theend surfaces include a front surface and a rear surface that areoppositely arranged, and an outer peripheral wall of the substrate is aside surface of the substrate; an area formed by projection of themagnetic core on the front surface or rear surface of the substrate isan area in which the magnetic core is located; the first end-surfaceconductor is arranged on the front surface of the substrate, and thesecond end-surface conductor is arranged on the rear surface of thesubstrate; the winding conductor has at least two turns, including afirst turn of the winding conductor and a second turn of the windingconductor, a first electronic component is arranged on the front surfaceof the substrate, and the magnetic core is horizontally arranged, wherethe first electronic component is located outside the area in which themagnetic core is located; the winding conductor includes a first turn ofthe winding conductor and a second turn of the winding conductor, afirst electronic component is arranged on the front surface of thesubstrate, where the first electronic component is located outside thearea in which the magnetic core is located, and a plated-through holepenetrating through the substrate is arranged within the area in whichthe magnetic core is located; the first end-surface conductor of thefirst turn of the winding conductor is connected to the first electroniccomponent, extends to a side wall of the plated-through hole, and isconnected to the first side-surface conductor of the first turn of thewinding conductor, the first side-surface conductor of the first turn ofthe winding conductor is a first conductive layer that is arranged onthe side wall of the plated-through hole, the first end-surfaceconductor of the first turn of the winding conductor is electricallyconductive to a metal layer on the rear surface of the substrate throughthe first conductive layer, the second end-surface conductor of thefirst turn of the winding conductor is connected to the firstside-surface conductor of the first turn of the winding conductor andextends to the side surface of the substrate, and the secondside-surface conductor of the first turn of the winding conductor isarranged on the side surface of the substrate and connected to thesecond end-surface conductor of the first turn of the winding conductor;the first end-surface conductor of the second turn of the windingconductor is connected to the second side-surface conductor of the firstturn of the winding conductor and extends to the side wall of theplated-through hole, the first side-surface conductor of the second turnof the winding conductor is a second conductive layer that is arrangedon the side wall of the plated-through hole, the first end-surfaceconductor of the second turn of the winding conductor is electricallyconductive to the metal layer on the rear surface of the substratethrough the second conductive layer, the second end-surface conductor ofthe second turn of the winding conductor is connected to the firstside-surface conductor of the second turn of the winding conductor andextends to the side surface of the substrate, and the secondside-surface conductor of the second turn of the winding conductor isarranged on the side surface of the substrate and connected to thesecond end-surface conductor of the second turn of the windingconductor.

With reference to the first aspect, in a tenth possible implementationmanner, top and bottom ends of the substrate are end surfaces, where theend surfaces include a front surface and a rear surface, and an outerperipheral wall of the substrate is a side surface of the substrate; anarea formed by the magnetic core on the front surface or rear surface ofthe substrate is an area in which the magnetic core is located; thewinding conductor includes a first turn of the winding conductor and asecond turn of the winding conductor, a first electronic component isarranged on the front surface of the substrate, and the magnetic core isvertically arranged; there is a conductor layer inside the substrate;the first end-surface conductor of the first turn of the windingconductor includes a first section of an conductor that is connected tothe first electronic component and located on the front surface of thesubstrate and a second section of the conductor that is connected to thefirst section of the conductor and electrically conductive to the innerlayer of the substrate, where the second section of the conductor is theconductor layer that is arranged on the inner layer of the substrate,and the conductor layer is located between the front surface and therear surface of the substrate; a third conductive via hole adjacent tothe magnetic core is arranged on the substrate, the first side-surfaceconductor of the first turn of the winding conductor is connected to thesecond section of the conductor and electrically conductive to the thirdconductive via hole within the area in which the magnetic core islocated, the second end-surface conductor of the first turn of thewinding conductor is connected to the first side-surface conductor ofthe first turn of the winding conductor and penetrates through themagnetic core, the second side-surface conductor of the first turn ofthe winding conductor is connected to the second end-surface conductorof the first turn of the winding conductor and electrically conductiveto a front surface of the substrate; the first end-surface conductor ofthe second turn of the winding conductor is connected to the secondside-surface conductor of the first turn of the winding conductor, thefirst side-surface conductor of the second turn of the winding conductoris a conductive via hole that is connected to the first end-surfaceconductor of the second turn of the winding conductor and electricallyconductive to the area in which the magnetic core is located, the secondend-surface conductor of the second turn of the winding conductor isconnected to the first side-surface conductor of the second turn of thewinding conductor and penetrates through the magnetic core, the secondside-surface conductor of the second turn of the winding conductor isconnected to the second end-surface conductor of the second turn of thewinding conductor and electrically conductive to the front surface ofthe substrate.

According to a second aspect, the present invention provides a powerconversion apparatus. The power conversion apparatus includes theforegoing circuit board, where a capacitor, a resistor, and a controlmodule that is configured to generate a control signal are arranged onthe circuit board, where the capacitor, the resistor, and the controlmodule are all connected to the substrate.

According to the circuit board and the power conversion apparatus havingthe circuit board provided by the present invention, the magnetic coreis embedded and different manners of winding the magnetic core are used,which may reduce the usage area of the substrate and flexibly use a wirerouting space of the conductive layer of the substrate. The windingconductor may flexibly traverse the surface and inside of the substrate,and both the shape of the magnetic core and the number of turns of thewinding conductor may be flexibly set according to actual conditions,where larger inductance may be designed according to an actual conditionto improve inductance consistency. The magnetic core is embedded intothe substrate, with no need of arranging a shield layer or encapsulatingelectronic components on the substrate. In this way, materials aresaved, the process is simplified, and the fabrication cost is reduced,thereby achieving an objective of saving materials and reducing the costfor fabricating a power conversion apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1a is a three-dimensional schematic diagram of a circuit boardaccording to Embodiment 1 of the present invention;

FIG. 1b is a sectional schematic diagram of a circuit board according toEmbodiment 1 of the present invention;

FIG. 2 is a three-dimensional schematic diagram of a circuit boardaccording to Embodiment 2 of the present invention;

FIG. 3 is a three-dimensional schematic diagram of a circuit boardaccording to Embodiment 3 of the present invention;

FIG. 4 is a sectional schematic diagram of the circuit board illustratedin FIG. 3;

FIG. 5 is another sectional schematic diagram of the circuit boardillustrated in FIG. 3;

FIG. 6 is a three-dimensional schematic diagram of a circuit boardaccording to Embodiment 3 of the present invention;

FIG. 7 is a three-dimensional schematic diagram of the magnetic core andthe winding conductor illustrated in FIG. 6;

FIG. 8 is a sectional schematic diagram of the circuit board illustratedin FIG. 6;

FIG. 9 is a three-dimensional schematic diagram of a circuit boardaccording to Embodiment 3 of the present invention;

FIG. 10 is a three-dimensional schematic diagram of the magnetic coreand the winding conductor illustrated in FIG. 9;

FIG. 11 is a sectional schematic diagram of the circuit boardillustrated in FIG. 9;

FIG. 12 is a three-dimensional schematic diagram of a circuit boardaccording to Embodiment 3 of the present invention;

FIG. 13 is a three-dimensional schematic diagram of the magnetic coreand the winding conductor illustrated in FIG. 12;

FIG. 14 is a sectional schematic diagram of the circuit boardillustrated in FIG. 11; and

FIG. 15 is a schematic diagram of a circuit of a power conversionapparatus according to Embodiment 4 of the present invention.

DETAILED DESCRIPTION

To make the objectives, technical solutions, and advantages of thepresent invention clearer, the following further describes in detail thepresent invention with reference to the accompanying drawings andembodiments. It should be understood that the specific embodimentsdescribed herein are merely provided to illustrate the presentinvention, and are not intended to limit the present invention.

Embodiment 1

As illustrated in FIG. 1a and FIG. 1b , an embodiment of the presentinvention provides a circuit board, including a substrate 8 and amagnetic core 3, where the magnetic core 3 is embedded into thesubstrate 8. The magnetic core 3 is in an annular shape, and themagnetic core 3 has an inner side and an outer side. The inner siderefers to an area enclosed by an inner peripheral wall of the magneticcore 3, and the outer side refers to an area outside an outer peripheralwall of the magnetic core 3. It can be understood that, the magneticcore 3 may be in a closed annular shape, or in an open annular shape. Ina practical application, a slot may be arranged on the substrate 8, themagnetic core 3 may be placed in the slot, and the slot is filled by amaterial so that the magnetic core 3 is embedded into the substrate 8.

As illustrated in FIGS. 1a and 1b , at least one turn of a windingconductor wound around the magnetic core 3 is arranged on the substrate8, where each turn of the winding conductor includes a first end-surfaceconductor 41 and a second end-surface conductor 42 that are separatelyarranged on two ends of the magnetic core 3, and each turn of thewinding conductor further includes a first side-surface conductor 43that penetrates through or penetrates through and arranged on the innerside of the magnetic core 3, and a second side-surface conductor 44 thatis arranged on the outer side of the magnetic core 3. The secondside-surface conductor 44 penetrates through the magnetic core 3 fromthe outer side of the magnetic core 3. The first side-surface conductor43 is electrically connected to the first end-surface conductor 41 andthe second end-surface conductor 42, the second side-surface conductor44 is electrically connected to the first end-surface conductor 41 orthe second end-surface conductor 42. In this way, the first end-surfaceconductor 41, the first side-surface conductor 43, the secondend-surface conductor 42, and the second side-surface conductor 44 mayform a turn of the winding conductor wound around the magnetic core 3.The number of turns of the winding conductor may be set according to anactual condition and may be two or more than two. Moreover, the magneticcore 3 may be in an annular shape, a framework shape, a “U” shape, an“E” shape, or a like proper shape. According to the embodiments of thepresent invention, the winding conductors may be all conveniently woundaround the magnetic core 3, and the shape of the magnetic core 3 and thenumber of turns of the winding conductor may be flexibly set accordingto an actual condition. An inductance value of the magnetic core 3 maybe set to a larger value to perfectly meet an actual usage requirement.In addition, the magnetic core 3 is embedded into the substrate 8, withno need of arranging a shield layer or encapsulating electroniccomponents on the substrate 8. In this way, the fabrication cost is low.

Specifically, as illustrated in FIG. 1a and FIG. 1b , the firstend-surface conductor 41 is arranged on one end surface of the substrate8, and the second end-surface conductor 42 is arranged on the other endsurface of the substrate 8. The substrate 8 has a front surface and arear surface that are oppositely arranged. The first end-surfaceconductor 41 may be located on the front surface of the substrate 8, andthe second end-surface conductor 42 may be located on the rear surfaceof the substrate 8. Certainly, the first end-surface conductor 41 mayalso be located inside the substrate 8 and located on one side of themagnetic core 3, and the second end-surface conductor 42 may also belocated inside the substrate 8 and located on the other side of themagnetic core 3, where the first end-surface conductor 41 and the secondend-surface conductor 42 may be both arranged in a spaced-apart mannerwith respect to the magnetic core 3. It can be understood that, in thisembodiment, the first end-surface conductor 41 and the secondend-surface conductor 42 may be located on the same layer of thesubstrate 8, or may be separately located on different step-like layersof the substrate 8, where adjacent layers may be connected by aconductive via hole.

Specifically, as illustrated in FIG. 1a and FIG. 1b , a first via holeis arranged on the substrate 8, where the first via hole is located onthe inner side of the magnetic core 3, the first side-surface conductor43 is a conductor filled in the first via hole, and the first via holeand the conductor filled or plated in the first via hole form aconductive via hole, so as to implement a function of layer exchanging(that is, electrical conduction; the layer exchanging is a commonly usedterm in the field of PCB technologies and used to implement signalcommunication between different layers). The conductive via hole is alsoreferred to as the via hole, which is a hole for electrical connectionbetween a plurality of layers of a PCB board (Printed Circuit Board,printed circuit board), and connects printed wires between layers. Theconductive via hole may be fabricated by using the plating copperprocess. Certainly, it can be understood that, a manner of layerexchanging may be layer exchanging from the front surface of thesubstrate 8 to the rear surface of the substrate 8 or to an inner metallayer of the substrate 8, and alternatively from one inner metal layerof the substrate 8 to another inner metal layer.

As illustrated in FIG. 1a and FIG. 1b , in this embodiment,specifically, top and bottom ends of the substrate 8 are end surfaces,where the end surfaces include a front surface and a rear surface thatare oppositely arranged, and an outer peripheral wall of the substrate 8is a side surface of the substrate 8. An area formed by projection ofthe magnetic core 3 on the front surface or rear surface of thesubstrate 8 is an area in which the magnetic core 3 is located. Thefirst end-surface conductor 41 is arranged on the front surface of thesubstrate 8, and the second end-surface conductor 42 is arranged on therear surface of the substrate 8. The winding conductor includes a firstturn of the winding conductor and a second turn of the windingconductor, and certainly, may further include more turns of the windingconductor: a third turn of the winding conductor, a fourth turn of thewinding conductor, and so on, which are set as required. A firstelectronic component 1 is arranged on the front surface of the substrate8, where the first electronic component 1 may be a chip. The magneticcore 3 is horizontally embedded into the substrate 8, and the magneticcore 3 is in an annular shape. The first electronic component 1 islocated outside the area in which the magnetic core 3 is located. Inthis embodiment, the expression “the area in which the magnetic core 3is located” refers to an area formed by projection of the magnetic core3 on the substrate 8 along an axial direction. The first end-surfaceconductor 41 of the first turn of the winding conductor is connected tothe first electronic component 1 and extends, in a wire routing manner,to the area in which the magnetic core 3 is located. The firstside-surface conductor 43 of the first turn of the winding conductor isa first conductive via hole. The first end-surface conductor 41 of thefirst turn of the winding conductor is vertically layer-exchanged to ametal layer on the rear surface of the substrate 8 by using the firstside-surface conductor 43 of the first turn of the winding conductor.The second end-surface conductor 42 of the first turn of the windingconductor is connected to the first side-surface conductor 43 of thefirst turn of the winding conductor, extends to the side surface of thesubstrate 8 in a wire routing or layout manner, and is connected to thesecond side-surface conductor 44. The second side-surface conductor 44of the first turn of the winding conductor is arranged on the sidesurface of the substrate 8 and connected to the second end-surfaceconductor 42 of the first turn of the winding conductor, thereby forminga turn of the winding conductor. The first end-surface conductor 41′ ofthe second turn of the winding conductor is connected to the secondend-surface conductor 42 of the first turn of the winding conductor andextends to the area in which the magnetic core 3 is located. The firstside-surface conductor 43′ of the second turn of the winding conductoris a second conductive via hole. The first end-surface conductor 41′ ofthe second turn of the winding conductor is vertically layer-exchangedto the metal layer on the rear surface of the substrate 8 by using thefirst side-surface conductor 43′ of the second turn of the windingconductor. The second end-surface conductor 42′ of the second turn ofthe winding conductor is connected to the first side-surface conductor43′ of the second turn of the winding conductor and extends to the sidesurface of the substrate 8. The second side-surface conductor 44′ of thesecond turn of the winding conductor is arranged on a side wall of thesubstrate 8 and connected to the second end-surface conductor 42′ of thesecond turn of the winding conductor, thereby forming another turn ofthe winding conductor. In addition, another electronic component may beconnected to the second side-surface conductor 44′ by a copper sheetthat is arranged on the front surface of the substrate 8. Certainly, ona basis of the second turn of the winding conductor, the proper numberof turns, such as the third turn of the winding conductor and the fourthturn of the winding conductor may further be set, and a secondelectronic component 2 is connected to the last turn of the windingconductor.

Embodiment 2

Alternatively, as illustrated in FIG. 2, as an alternative solution forthe first and second conductive via holes in Embodiment 1, a firstplated-through hole 81 penetrates through and arranged on the inner sideof the magnetic core 3 is arranged on the substrate 8, where the firstplated-through hole 81 penetrates through the substrate and penetratesthrough an inner ring of the magnetic core 3. The first side-surfaceconductor 43 is a conductor that is plated on an inner side wall of thefirst plated-through hole 81, where the conductor is in a strip shapeand two ends of the conductor are aligned with the front surface and therear surface of the substrate 8. The first side-surface conductor 43 maybe directly layer-exchanged to the other surface of the substrate 8. Thecorresponding number of conductors may be arranged on an inner side ofthe first plated-through hole 81 according to the number of turns of thewinding conductor. In a practical application, the first plated-throughhole 81 may be in a circular shape, a polygonal shape, or a like propershape. In this embodiment, the magnetic core 3 may be in a rectangleframework shape, the first plated-through hole 81 is correspondingly ina rectangular shape, so that the conductor is plated on a side wall ofthe first plated-through hole 81. Certainly, it can be understood that,the first plated-through hole 81 may be a straight hole, a step-likehole, or another proper type of hole. If the first plated-through hole81 is a step-like hole, correspondingly the conductor on the inner sideof the first plated-through hole 81 is also in a step-like shape.

As an alternative solution, a second via hole (not illustrated in thefigure) is arranged on the substrate 8, where the second via hole islocated on an outer side of the magnetic core 3, and the secondside-surface conductor 44 is a conductor filled in the second via hole.The second via hole and the conductor filled or plated in the second viahole form a conductive via hole, so as to implement a function of layerexchanging. Certainly, it can be understood that, a manner of layerexchanging may be layer exchanging from the front surface of thesubstrate 8 to the rear surface of the substrate 8 or to an inner metallayer of the substrate 8, and alternatively from one inner metal layerof the substrate 8 to another inner metal layer. Alternatively, as analternative solution for a solution in which the second side-surfaceconductor is a conductive via hole, a second plated-through hole (notillustrated in the figure) is arranged on the substrate 8, where thesecond plated-through hole is located on the outer side of the magneticcore 3, and the second side-surface conductor 44 is a conductor that isplated on an inner side wall of the second plated-through hole.

It can be understood that, an electronic component, for example, a chip,a capacitor, or the like, on the substrate 8 may also be directlyconnected to the conductive via hole.

In this embodiment, the second side-surface conductor 44 is a conductorthat is plated on the side wall of the substrate 8, the secondside-surface conductor 44 may be in a strip shape, where two ends of theconductor are aligned with the front surface and the rear surface of thesubstrate 8. In this way, the substrate 8 is fully utilized, thefabrication process is simplified, and the cost is reduced.

In a practical application, the magnetic core 3 may be vertically,horizontally, or even slantingly embedded into the substrate 8.Correspondingly, a straight wire manner of the winding conductor iscorrespondingly changed.

Specifically, the magnetic core 3 may be in an annular shape, and themagnetic core 3 may have a plurality of head-tail connected edges. Forexample, the magnetic core may be in a polygonal annular shape, in anannular shape, in a track shape, or in a special shape; or in a combinedshape of a “U” shape and an “I” shape, a combined shape of an “E” shapeand an “I” shape, or a combined shape of an “E” shape and another “E”shape. There is a wide selection for the magnetic core 3, and thereforelarger inductance may be achieved.

In this embodiment, the magnetic core 3 is in a polygonal annular shape.Using the magnetic core 3 in a rectangular framework shape as anexample, the winding conductor has at least two turns, and all thewinding conductor may be wound around the same edge of the magnetic core3. Alternatively, at least one turn is wound opposite one edge of themagnetic core 3, and at least another one turn is wound opposite,adjacently, or spaced-apart from another edge of the magnetic core 3. Aspecific winding manner may be set according to an actual condition,thereby achieving higher flexibility and larger inductance.

Specifically, the substrate 8 has a front surface and a rear surfacethat are oppositely arranged. The first end-surface conductor 41 isarranged on the front surface of the substrate 8. The second end-surfaceconductor 42 is arranged on the rear surface of the substrate 8. Thewinding conductor includes a first turn of the winding conductor and asecond turn of the winding conductor. A first electronic component 1 isarranged on the front surface of the substrate 8. The magnetic core 3 ishorizontally arranged. The first electronic component 1 is locatedoutside an area in which the magnetic core 3 is located. The firstend-surface conductor 41 of the first turn of the winding conductor isconnected to the first electronic component 1 and extends to a side wallof the plated-through hole 81. The first side-surface conductor 43 ofthe first turn of the winding conductor is a first conductive layer thatis arranged on the side wall of the plated-through hole 81. The firstend-surface conductor 41 of the first turn of the winding conductor iselectrically conductive to a metal layer on the rear surface of thesubstrate 8 by using the first side-surface conductor 43 of the firstturn of the winding conductor. The second end-surface conductor 42 ofthe first turn of the winding conductor is connected to the firstside-surface conductor 43 of the first turn of the winding conductor andextends to the side surface of the substrate 8. The second side-surfaceconductor 44 of the first turn of the winding conductor is arranged onthe side wall of the substrate 8 and connected to the second end-surfaceconductor 42 of the first turn of the winding conductor. The firstend-surface conductor 41′ of the second turn of the winding conductor isconnected to the second side-surface conductor 44 of the first turn ofthe winding conductor and extends to the side wall of the plated-throughhole 81. The first side-surface conductor 43′ of the second turn of thewinding conductor is a second conductive layer that is arranged on theside wall of the plated-through hole 81. The first end-surface conductor41′ of the second turn of the winding conductor is electricallyconductive to a metal layer on rear back surface of the substrate 8 byusing the first side-surface conductor 43′ of the second turn of thewinding conductor. The second end-surface conductor 42′ of the secondturn of the winding conductor is connected to the first side-surfaceconductor 43′ of the second turn of the winding conductor and extends tothe side surface of the substrate 8. The second side-surface conductor44′ of the second turn of the winding conductor is arranged on the sidewall of the substrate 8 and connected to the second end-surfaceconductor 42′ of the second turn of the winding conductor.

Embodiment 3

As illustrated in FIG. 3 to FIG. 5, different from the foregoingembodiments, in this embodiment, a magnetic core 3 is verticallyembedded into a substrate 8.

Top and bottom ends of the substrate 8 are end surfaces. The endsurfaces include a front surface and a rear surface that are oppositelyarranged. An outer peripheral wall of the substrate 8 is a side surfaceof the substrate. An area formed by the magnetic core 3 on the frontsurface or rear surface of the substrate 8 is an area in which themagnetic core is located. An inner layer of the substrate 8 has aconductor layer. A first end-surface conductor 41 is arranged on thefront surface of the substrate 8. A second end-surface conductor 42 isarranged on the rear surface of the substrate 8. A winding conductorincludes a first turn of the winding conductor and a second turn of thewinding conductor. A first electronic component 1 is arranged on thefront surface of the substrate 8. The first end-surface conductor 41 ofthe first turn of the winding conductor includes a first section of aconductor 411 that is connected to the first electronic component 1 andlocated on the front surface of the substrate 8 and a second section ofthe conductor 412 that is connected to the first section of theconductor 411 and electrically conductive to the inside of the substrate8. A first side-surface conductor 43 of the first turn of the windingconductor is a third conductive via hole that is connected to the secondsection of the conductor 412 and electrically conductive to the area inwhich the magnetic core 3 is located. The second end-surface conductor42 of the first turn of the winding conductor is connected to the firstside-surface conductor 43 of the first turn of the winding conductor andpenetrates through the inner side of the magnetic core 3. A secondside-surface conductor 44 of the first turn of the winding conductor isconnected to the second end-surface conductor 42 of the first turn ofthe winding conductor and electrically conductive to a front surface ofthe substrate. A first end-surface conductor 41′ of the second turn ofthe winding conductor is connected to the second side-surface conductor44 of the first turn of the winding conductor and crosses the outer sideof the magnetic core 3. A first side-surface conductor 43′ of the secondturn of the winding conductor is a fourth conductive via hole that isconnected to the first end-surface conductor 41′ of the second turn ofthe winding conductor and electrically conductive to the area in whichthe magnetic core 3 is located. A second end-surface conductor 42′ ofthe second turn of the winding conductor is connected to the firstside-surface conductor 43 of the first turn of the winding conductor andpenetrates through the inner side of the magnetic core 3. A secondside-surface conductor 44′ of the second turn of the winding conductoris connected to the second end-surface conductor 42′ of the second turnof the winding conductor and electrically conductive to the frontsurface of the substrate. Related electronic components such ascapacitors may be connected to the second end-surface conductor 42′ by acopper sheet. Certainly, the proper number of turns of the windingconductor, such as a third turn of the winding conductor and a fourthturn of the winding conductor, may further be set according to an actualcondition. The winding conductor may also be designed with only oneturn.

As illustrated in FIG. 6 to FIG. 8, the winding conductor may be woundaround a side column of the magnetic core 3. The wound wire within thesame turn is located at two different layers, an upper layer and a lowerlayer, and the wound wire within different turns is located at the samelayer.

It can be understood that, as illustrated in FIG. 9 to FIG. 11, themagnetic core 3 stands in the substrate 8. The winding (that is, thewinding conductor) is formed by a copper sheet, a via hole or a sidewall plating, and is wound around two different side columns (an upperside column and a lateral side column of the magnetic core 3) of themagnetic core 3. One turn of the winding conductor is wound around theupper side column of the magnetic core 3, and the other turn of thewinding conductor is wound around a lower side column of the magneticcore 3. As illustrated in FIG. 12 to FIG. 14, the magnetic core 3 standsin the substrate 8. The winding (that is, the winding conductor) isformed by a copper sheet, a via hole or a side wall plating, and iswound around two different side columns (an upper side column and alateral side column of the magnetic core 3) of the magnetic core 3. Oneturn of the winding conductor is wound around the upper side column ofthe magnetic core 3, and the other turn of the winding conductor iswound around the lateral side column of the magnetic core 3. Themagnetic core 3 may be vertically or horizontally embedded into thesubstrate 8. The winding manner of embedding the magnetic core 3 isdiversified. The winding conductor may be a combination of an extensionof a conductive metal layer and a via hole, or may be a combination ofthe extension of the conductive metal layer and a plated metal layer onthe side wall of the substrate 8, or may be a combination of theextension of the conductive metal layer, the plated metal layer on theside wall of the substrate 8, and a conductive via hole on the substrate8. The number of winding turns may be a random value. The column of themagnetic core 3 around which each turn is wound may be the upper sidecolumn of the magnetic core 3, or may be the lower side column, or maybe the lateral side column. The turns of the winding conductor may bewound around the same side column of the magnetic core, or may be woundaround an opposite or adjacent side column of the magnetic core.

Embodiment 4

As illustrated in FIG. 15, an embodiment of the present inventionprovides a power conversion apparatus. The power conversion apparatusincludes the foregoing circuit board. A capacitor, a resistor, and acontrol module (control IC) that is configured to generate a controlsignal are arranged on the circuit board, where the capacitor, theresistor, and the control module are all connected to the substrate, andthe capacitor, the resistor, and the control module are located on thesame surface or different surfaces of the circuit board. Specifically,the control module is configured to generate a control signal to drivean internal or external power switch component to perform acorresponding switch-on or switch-off action and generate a desiredelectrical pulse signal. The foregoing circuit board, in collaborationwith the capacitor, is configured to smooth the pulse signal generatedby the switch component, and meanwhile store electromagnetic energy. Inthis way, the entire apparatus works collaboratively and sequentially togenerate expected voltage and current signals and supply power topowered devices.

Specifically, as illustrated in FIG. 15, within a block enclosed by thebold solid lines, a schematic diagram of the power conversion apparatusin this embodiment is given. In FIG. 15, V1 is a direct current powersupply that supplies power to the power conversion apparatus in thisembodiment, and R1 is a powered device connected to a rear end of thepower conversion apparatus in this embodiment. In FIGS. 15, Q1 and Q2are power switch components, which may be integrated into a control chipand correspond to the first electronic component 1 in the foregoingfigures; and La is the magnetic core; C1 is the second electroniccomponent 2.

The power conversion apparatus has a magnetic core 3 embedded into thesubstrate 8, a power supply IC apparatus, a capacitor, and otherelectronic components.

Alternatively, the power conversion apparatus has a magnetic core 3embedded into the substrate 8, a power supply IC apparatus, a powerswitch component, a capacitor, other electronic components, and thelike.

The power conversion apparatus is connected to other electronic devicesby using the following forms of pins: BGA ball-shaped pins, surfacemounted weld pad, castle-shaped pins, and the like, which, however, arenot limited to such listed forms.

Certainly, it can be understood that, the foregoing circuit board mayalso be applicable to other electronic devices in addition to the powerconversion apparatus.

Embodiment 5

An embodiment of the present invention further provides a method forfabricating a circuit board, including the following steps: withreference to FIG. 1a and FIG. 1b , preparing the substrate 8 and themagnetic core 3; opening a slot on the substrate 8 and embedding themagnetic core 3 into the substrate 8; arranging the first end-surfaceconductor 41, which is located on one side of the magnetic core 3, onthe substrate 8; arranging the first side-surface conductor 43, whichpenetrates through the magnetic core 3 from the inner side of themagnetic core 3 and is connected to the first end-surface conductor 41,on the substrate 8; arranging the second end-surface conductor 42, whichis located on the other side of the magnetic core 3, on the substrate 8;arranging the second side-surface conductor 44, which penetrates throughthe magnetic core 3 from the outer side of the magnetic core 3 and isconnected to the second end-surface conductor 42, on the substrate 8,where the first end-surface conductor 41, the first side-surfaceconductor 43, the second end-surface conductor 42, and the secondside-surface conductor 44 may form a turn of the winding conductor thatis wound around the magnetic core 3. Specifically, a winding conductorwith the proper number of turns may be set according to an actualcondition.

Specifically, the first end-surface conductor 41 and the secondend-surface conductor 42 may be arranged on the end surface of thesubstrate 8; the first end-surface conductor 41 and the secondend-surface conductor 42 may be copper sheets, which may be formed in amanner such as etching.

Specifically, the first side-surface conductor 43 may be a conductivevia hole, which may implement layer exchanging for signals. In apractical application, a hole may be drilled on the substrate 8, and aconductive material may be plated in the hole, where the conductivematerial may be copper or the like. The foregoing conductive via holemay be a blind via, a buried via, or a plated-through hole. The blindvia is located on a surface of a top layer and a bottom layer of aprinted circuit board, and has a specific depth. The blind via is usedfor connection of wires at an outer layer and wires at a lower innerlayer. The buried via refers to a connection hole that is located on theinner layer of the printed circuit board, which does not extend to thesurface of the circuit board. The foregoing two types of vias are bothlocated on the inner layer of the circuit board. Before lamination, thevias are fabricated by using the plated-through hole formation process.During formation of the via hole, several inner layers may further befabricated in an overlapping manner. The third type of hole is referredto as the plated-through hole. This type of hole penetrates through theentire circuit board, and may be used to implement internalinterconnection or may be used as an installation pilot hole for acomponent.

Alternatively, with reference to FIG. 2, as an alternative solution forthe conductive via hole, a plated-through hole penetrating through thesubstrate 8 and the center of the magnetic core 3 may be arranged, withrespect to the area in which the magnetic core 3 is located, on thesubstrate 8; the first side-surface conductor 43 may be in a strip shapeand plated on a side wall of the plated-through hole, or may alsoimplement layer exchanging for signals. Likewise, the secondside-surface conductor 44 may also be a conductive plated-through holethat is arranged on the substrate 8 and located on an outer side of thearea in which the magnetic core 3 is located; alternatively, aplated-through hole penetrating through the substrate 8 may be arranged,with respect to the area in which the magnetic core 3 is located, on thesubstrate 8, and the second side-surface conductor 44 may be in a stripshape and plated on a side wall of the plated-through hole. In addition,the second side-surface conductor 44 may also be in a strip shape andplated on a side wall of the substrate 8.

The winding conductor may be formed by a combination of a copper sheetin combination with side-wall plating, or a steel sheet in combinationwith a conductive via hole, side-wall plating, and a via hole.

Specifically, a slot is arranged on the substrate 8, the magnetic core 3is embedded into the slot on the substrate 8, and an electroniccomponent, such as a chip and the like, is arranged on the front surfaceof the substrate 8.

In a first manner, with reference to FIG. 1a and FIG. 1b , using a casein which the magnetic core 3 is horizontally embedded into the substrate8 as an example, the first electronic component 1 (a first chip) on theupper surface of the substrate 8 is led, through the first end-surfaceconductor 41 formed by a conductive copper sheet, into an area enclosedby an inner ring of the annular magnetic core 3 that is embedded intothe substrate 8, vertically penetrates through the substrate 8 to ametal layer on the rear surface of the magnetic core 3 through the firstside-surface conductor 43 formed by a conductive via hole, and extendsto an edge of the substrate 8 through the second end-surface conductor42 formed by the copper sheet on the layer. The second side-surfaceconductor 44 is formed by copper plating on the edge of the substrate 8by using the plating process, and is electrically conductive to a basemetal layer on the front surface of the magnetic core 3, extends to thearea enclosed by the inner ring of the magnetic core 3 through thecopper sheet, is electrically conductive to the metal layer on the rearsurface of the substrate 8 through the conductive via hole, extends tothe edge of the substrate 8 through the copper sheet on the metal layeron the rear surface of the substrate 8, is electrically conductive backto a metal layer on the front surface of the substrate 8 through aplated metal copper layer, and then extends from the copper sheet on themetal layer to the second electronic component 2 (the capacitor). Thewinding of two turns or more turns is implemented for the magnetic core3 according to the foregoing process, thereby achieving correspondinginductance.

In a second manner, with reference to FIG. 3 and FIG. 4, using a case inwhich the magnetic core 3 is vertically embedded into the substrate 8 asan example, the first end-surface conductor 41 that is formed by thecopper sheet and led out by the first electronic component 1 at themetal layer on the upper surface of the substrate 8 extends and iselectrically conductive to a conductive metal layer of the base materialthrough a conductive via hole (which may be a buried via, a blind via,or a plated-through hole), extends to the area enclosed by the magneticcore 3 through a conductive copper sheet, and is electrically conductiveto a metal layer in the area enclosed by the magnetic core 3 through theconductive via hole, extends through the copper sheet and horizontally(parallel to the upper side column of the magnetic core 3), penetratesthrough the area enclosed by the magnetic core 3, is electricallyconductive to a metal layer on the front surface of the substrate 8 byusing a conductive via hole, extends through the copper sheet that islocated on the front surface of the substrate 8 and horizontally(parallel to the upper side column of the magnetic core 3), penetratesthrough the upper surface of the upper side column of the magnetic core3, and is electrically conductive to the metal layer of the substrate 8in the area enclosed by the magnetic core 3 through the conductive viahole. At this layer, the copper sheet is led out from a conductive viahole 7, extends horizontally (parallel to the upper side column of themagnetic core 3), penetrates through the area enclosed by the magneticcore 3, and is then electrically conductive to a corresponding layer(generally a layer higher than the upper side column of the magneticcore 3). The winding of two turns or more turns is implemented for themagnetic core 3 according to the foregoing process, thereby achievingcorresponding inductance.

In a third manner, similar to the winding manner in the case in whichthe magnetic core 3 is vertically embedded into the substrate 8, thisembodiment further discloses another winding manner. With reference toFIG. 6, the winding process is similar to the foregoing process. FIG. 8is a sectional diagram thereof. The winding manner is characterized inthat the magnetic core 3 is embedded into the substrate 8, visually themagnetic core 3 stands in the substrate 8, and the winding is formed bya copper sheet, a via hole, or side-wall plating, where the windingconductor may be wound around a side column of the magnetic core 3, thewound wire within the same turn is located at two different layers, anupper layer and a lower layer, and the wound wire within different turnsis located at the same layer.

In a fourth manner, the winding process is similar to the foregoingprocess. FIG. 9 is a schematic diagram of the winding process, and FIG.11 is a sectional diagram thereof. The winding is characterized in thatthe magnetic core 3 is embedded into the substrate 8, visually themagnetic core 3 stands in the substrate 8, and the winding is formed bya copper sheet, a via hole, or side-wall plating, where the winding isperformed around two different side columns of the magnetic core 3(upper and lower side columns of the magnetic core 3), where one turn ofthe winding conductor is wound around the lower side column of themagnetic core 3, and the other turn of the winding conductor is woundaround the upper side column of the magnetic core 3.

In a fifth manner, the winding process is similar to the foregoingprocess. FIG. 12 is a schematic diagram of the winding process, and FIG.14 is a sectional diagram thereof. The winding is characterized in thatthe magnetic core 3 is embedded into the substrate 8, visually themagnetic core 3 stands in the substrate 8, and the winding is formed bya copper sheet, a via hole, or side-wall plating, where the winding isperformed around two different side columns of the magnetic core 3(upper and lateral side columns of the magnetic core 3), where one turnof the winding conductor is wound around the upper side column of themagnetic core 3, and the other turn of the winding conductor is woundaround the lateral side column of the magnetic core 3.

It can be understood that, in this embodiment, the arrangement mannerand the winding manner of the magnetic core 3 are not limited to themanners listed above. With respect to the magnetic core 3 that ishorizontally embedded into the substrate 8, the winding manner ofembedding the magnetic core 3 is diversified. The winding conductor maybe a combination of an extension of a conductive metal layer and a viahole, or may be a combination of the extension of the conductive metallayer and a plated metal layer on the side wall of the substrate 8, ormay be a combination of the extension of the conductive metal layer, theplated metal layer on the side wall of the substrate 8, and a conductivevia hole on the substrate 8. With respect to the magnetic core 3 that isvertically embedded into the substrate 8, the winding manner ofembedding the magnetic core 3 is diversified. The winding conductor maybe a combination of an extension of a conductive metal layer and a viahole, or may be a combination of the extension of the conductive metallayer and a plated metal layer on the side wall of the substrate 8, ormay be a combination of the extension of the conductive metal layer, theplated metal layer on the side wall of the substrate 8, and a conductivevia hole on the substrate 8. The number of winding turns may be a randomvalue. The column of the magnetic core 3 around which each turn is woundmay be an upper side column of the magnetic core 3, or may be a lowerside column, or may be a lateral side column. The turns may be woundaround the same side column of the magnetic core, or may be wound arounddifferent side columns of the magnetic core. According to the circuitboard, the power conversion apparatus having the circuit board, and themethod for fabricating the circuit board provided by the presentinvention, the magnetic core 3 is embedded and different manners ofwinding the magnetic core 3 are used, which may reduce the usage area ofthe substrate 8 and flexibly use a wire routing space of the conductivelayer of the substrate 8. Different turns may be wound as required,which achieves larger inductance, improves inductance consistency, savesmaterials, and reduces cost for fabricating a power conversionapparatus.

Specifically, the embedded magnetic core 3 may have an air gap or no airgap. With respect to the embedded magnetic core 3 having an air gap,during embedding of the magnetic core 3, fool-proofing design isrequired, and a direction of the air gap needs to be controlled. Forexample, a shear angle, an asymmetrical design for the magnetic core 3,and the like are used.

A material of the magnetic core 3 may be a ferrite, a metal power core,an amorphous alloy, a permanent magnet, or a like proper material.

The foregoing descriptions are merely preferred embodiments of thepresent invention, but are not intended to limit the present invention.Any modifications, equivalent replacements, or improvements made withoutdeparting from the spirit and principle of the present invention shallfall within the protection scope of the present invention.

What is claimed is:
 1. A circuit board, comprising: a substrate and amagnetic core, wherein the magnetic core is in an annular shape and themagnetic core has an inner side and an outer side, wherein the magneticcore is embedded into the substrate, at least one turn of a windingconductor wound around the magnetic core is arranged on the substrate,each turn of the winding conductor comprises a first end-surfaceconductor and a second end-surface conductor that are separatelyarranged on two ends of the magnetic core, and each turn of the windingconductor further comprises a first side-surface conductor thatpenetrates through the inner side of the magnetic core and a secondside-surface conductor that is arranged on the outer side of themagnetic core, wherein the first side-surface conductor is electricallyconnected to the first end-surface conductor and the second end-surfaceconductor, and the second side-surface conductor is electricallyconnected to the second end-surface conductor, wherein the secondside-surface conductor is disposed on the surface of the lateral side ofthe substrate.
 2. The circuit board according to claim 1, wherein thefirst end-surface conductor is arranged on one end surface of thesubstrate, and the second end-surface conductor is arranged on the otherend surface of the substrate.
 3. The circuit board according to claim 1,wherein: a first via hole is arranged on the substrate and located onthe inner side of the magnetic core, and the first side-surfaceconductor is a conductor filled in the first via hole; or a firstplated-through hole that penetrates through and arranged on the innerside of the magnetic core is arranged on the substrate, and the firstside-surface conductor is a conductor that is plated on an inner sidewall of the first plated-through hole.
 4. The circuit board according toclaim 1, wherein: a second via hole is arranged on the substrate andlocated on the outer side of the magnetic core, and the secondside-surface conductor is a conductor filled in the second via hole; ora second plated-through hole is arranged on the substrate, wherein thesecond plated-through hole is located on the outer side of the magneticcore, and the second side-surface conductor is a conductor that isplated on an inner side wall of the second plated-through hole.
 5. Thecircuit board according to claim 1, wherein the second side-surfaceconductor is a conductor plated on a side wall of the substrate.
 6. Thecircuit board according to claim 1, wherein the magnetic core isvertically or horizontally embedded into the substrate.
 7. The circuitboard according to claim 1, wherein the magnetic core has an annularshape, a polygonal annular shape, a combined shape of a “U” shape and an“I” shape, a combined shape of an “E” shape and an “I” shape, or acombined shape of an “E” shape and another “E” shape.
 8. The circuitboard according to claim 1, wherein: the magnetic core has a polygonalannular shape and a plurality of head-tail connected edges; and thewinding conductor has at least two turns, wherein at least one turn ofthe winding conductor is wound around one edge of the magnetic core andat least the other one turn of the winding conductor is wound aroundanother edge of the magnetic core, or all the winding conductor is woundaround a same edge of the magnetic core.
 9. The circuit board accordingto claim 1, wherein: top and bottom ends of the substrate are endsurfaces, wherein the end surfaces comprise a front surface and a rearsurface that are oppositely arranged, and an outer peripheral wall ofthe substrate is a side surface of the substrate; an area formed byprojection of the magnetic core on the front surface or rear surface ofthe substrate is an area in which the magnetic core is located; thefirst end-surface conductor is arranged on the front surface of thesubstrate, and the second end-surface conductor is arranged on the rearsurface of the substrate; the winding conductor has at least two turns,and the winding conductor comprises a first turn of the windingconductor and a second turn of the winding conductor, a first electroniccomponent is arranged on the front surface of the substrate, and themagnetic core is horizontally arranged, wherein the first electroniccomponent is located outside the area in which the magnetic core islocated; and the first end-surface conductor of the first turn of thewinding conductor is connected to the first electronic component andextends to the area in which the magnetic core is located, the firstside-surface conductor of the first turn of the winding conductor is afirst conductive via hole, the first end-surface conductor of the firstturn of the winding conductor is electrically conductive to a metallayer on the rear surface of the substrate through the first conductivevia hole, the second end-surface conductor of the first turn of thewinding conductor is connected to the first side-surface conductor ofthe first turn of the winding conductor, extends to the side surface ofthe substrate, and is connected to the second side-surface conductor,and the second side-surface conductor of the first turn of the windingconductor is arranged on the side surface of the substrate and connectedto the second end-surface conductor of the second turn of the windingconductor; the first end-surface conductor of the second turn of thewinding conductor is connected to the second side-surface conductor ofthe first turn of the winding conductor and extends to the area in whichthe magnetic core is located, the first side-surface conductor of thesecond turn of the winding conductor is a second conductive via hole,the first end-surface conductor of the second turn of the windingconductor is electrically conductive to the metal layer on the rearsurface of the substrate through the second conductive via hole, thesecond end-surface conductor of the second turn of the winding conductoris connected to the first side-surface conductor of the second turn ofthe winding conductor and extends to the side surface of the substrate,and the second side-surface conductor of the second turn of the windingconductor is arranged on the side surface of the substrate and connectedto the second end-surface conductor of the first turn of the windingconductor.
 10. The circuit board according to claim 1, wherein: top andbottom ends of the substrate are end surfaces, wherein the end surfacescomprise a front surface and a rear surface that are oppositelyarranged, and an outer peripheral wall of the substrate is a sidesurface of the substrate; an area foamed by projection of the magneticcore on the front surface or rear surface of the substrate is an area inwhich the magnetic core is located; the first end-surface conductor isarranged on the front surface of the substrate, and the secondend-surface conductor is arranged on the rear surface of the substrate;the winding conductor has at least two turns, comprising a first turn ofthe winding conductor and a second turn of the winding conductor, afirst electronic component is arranged on the front surface of thesubstrate, and the magnetic core is horizontally arranged, wherein thefirst electronic component is located outside the area in which themagnetic core is located; a plated-through hole penetrating through thesubstrate is arranged within the area in which the magnetic core islocated; the first end-surface conductor of the first turn of thewinding conductor is connected to the first electronic component,extends to a side wall of the plated-through hole, and is connected tothe first side-surface conductor of the first turn of the windingconductor, the first side-surface conductor of the first turn of thewinding conductor is a first conductive layer arranged on the side wallof the plated-through hole, the first end-surface conductor of the firstturn of the winding conductor is electrically conductive to a metallayer on the rear surface of the substrate through the first conductivelayer, the second end-surface conductor of the first turn of the windingconductor is connected to the first side-surface conductor of the firstturn of the winding conductor and extends to the side surface of thesubstrate, and the second side-surface conductor of the first turn ofthe winding conductor is arranged on the side surface of the substrateand connected to the second end-surface conductor of the first turn ofthe winding conductor; and the first end-surface conductor of the secondturn of the winding conductor is connected to the second side-surfaceconductor of the first turn of the winding conductor and extends to theside wall of the plated-through hole, the first side-surface conductorof the second turn of the winding conductor is a second conductive layerarranged on the side wall of the plated-through hole, the firstend-surface conductor of the second turn of the winding conductor iselectrically conductive to the metal layer on the rear surface of thesubstrate through the second conductive layer, the second end-surfaceconductor of the second turn of the winding conductor is connected tothe second conductive layer and extends to the side surface of thesubstrate, and the second side-surface conductor of the second turn ofthe winding conductor is arranged on the side surface of the substrateand connected to the second end-surface conductor of the second turn ofthe winding conductor.
 11. The circuit board according to claim 1,wherein: top and bottom ends of the substrate are end surfaces, whereinthe end surfaces comprise a front surface and a rear surface that areoppositely arranged, and an outer peripheral wall of the substrate is aside surface of the substrate; an area formed by projection of themagnetic core on the front surface or rear surface of the substrate isan area in which the magnetic core is located; the winding conductor hasat least two turns, comprising a first turn of the winding conductor anda second turn of the winding conductor, a first electronic component isarranged on the front surface of the substrate, and the magnetic core isvertically arranged; an inner layer of the substrate has a conductorlayer; the first end-surface conductor of the first turn of the windingconductor comprises a first section of an conductor that is connected tothe first electronic component and located on the front surface of thesubstrate, and a second section of the conductor that is connected tothe first section of the conductor and electrically conductive to theinner layer of the substrate, wherein the second section of theconnector is the conductor layer arranged on the inner layer of thesubstrate, and the conductor layer is located between the front surfaceand the rear surface of the substrate; a third conductive via holeadjacent to the magnetic core is arranged on the substrate, the firstside-surface conductor of the first turn of the winding conductor isconnected to the second section of the conductor and electricallyconductive to the third conductive via hole, the second end-surfaceconductor of the first turn of the winding conductor is connected to thefirst side-surface conductor of the first turn of the winding conductorand penetrates through the magnetic core, the second side-surfaceconductor of the first turn of the winding conductor is connected to thesecond end-surface conductor of the first turn of the winding conductorand electrically conductive to a front surface of the substrate; and thefirst end-surface conductor of the second turn of the winding conductoris connected to the second side-surface conductor of the first turn ofthe winding conductor, the first side-surface conductor of the secondturn of the winding conductor is a fourth conductive via hole that isconnected to the first end-surface conductor of the second turn of thewinding conductor and electrically conductive to the area in which themagnetic core is located, the second end-surface conductor of the secondturn of the winding conductor is connected to the first side-surfaceconductor of the second turn of the winding conductor and penetratesthrough the magnetic core, the second side-surface conductor of thesecond turn of the winding conductor is connected to the secondend-surface conductor of the second turn of the winding conductor andelectrically conductive to the front surface of the substrate.
 12. Anapparatus comprising the circuit board according to claim 1, wherein acapacitor, a resistor, and a control module configured to generate acontrol signal are arranged on the circuit board, wherein the capacitor,the resistor, and the control module are all connected to the substrate.13. The apparatus according to claim 12, wherein the first end-surfaceconductor is arranged on one end surface of the substrate, and thesecond end-surface conductor is arranged on the other end surface of thesubstrate.
 14. The apparatus according to claim 12, wherein: a first viahole is arranged on the substrate and located on the inner side of themagnetic core, and the first side-surface conductor is a conductorfilled in the first via hole; or a first plated-through hole thatpenetrates through and arranged on the inner side of the magnetic coreis arranged on the substrate, and the first side-surface conductor is aconductor that is plated on an inner side wall of the firstplated-through hole.
 15. The apparatus according to claim 12, wherein: asecond via hole is arranged on the substrate and located on the outerside of the magnetic core, and the second side-surface conductor is aconductor filled in the second via hole; or a second plated-through holeis arranged on the substrate, wherein the second plated-through hole islocated on the outer side of the magnetic core, and the secondside-surface conductor is a conductor that is plated on an inner sidewall of the second plated-through hole.